Impact on wetlands a concern in bridge replacement

Environmental protection agencies are asking for more concrete plans for preserving wetlands before construction begins on a new Back River Bridge, connecting Savannah and Jasper County.

The U.S. Fish and Wildlife Service, Georgia Environmental Protection Division and the South Carolina Department of Natural Resources have questioned a plan to purchase tidal marsh mitigation credits from the Salt Creek Saltmarsh Mitigation Bank in Chatham County, Ga., before those credits are sure to be available.

The credits are a way of making up for destroying some wetlands by promising to preserve other, comparable land somewhere else.

The Georgia EPD says those credits need to be in hand on the front end of the construction, according to comments obtained last month from the Charleston District of the U.S. Army Corps of Engineers.

“There is no guarantee this bank will be approved or that the credits will be available. EPD is not comfortable with the ‘contractual agreement’ to purchase credits when they become available,” wrote Georgia EPD official Catherine Samay in January.

“The mitigation needs to occur at the same time as the construction activities/impacts, not sometime in the future.”

Until its environmental concerns are answered, wrote Georgia EPD, the 401 water quality certification application “is considered incomplete.”

The corps forwarded all the comments to both Georgia and South Carolina transportation departments, which are the applicants for the bridge replacement project. The corps is waiting for a response, said Elizabeth Williams a regulatory official in the corps’ Charleston District.

“It is the (their) responsibility to provide appropriate mitigation for the proposed impacts to waters of the U.S., and we will not issue a permit until appropriate mitigation has been identified,” said Williams, responding to questions Thursday.

On Friday a spokeswoman for the Georgia Department of Transportation had no information about any alternate strategies for compensating for the wetlands destruction.

But purchasing mitigation bank credits isn’t the only possible solution. Other ways to offset wetlands destruction include buying or using credits from an approved in-lieu fee program, and/or restoration, enhancement, creation or preservation of wetlands, according to the corps.

The about 100-acre mitigation bank is located within the Ogeechee Coastal/South Atlantic Coastal Watershed, northwest of Salt Creek and southeast of U.S. 17, according to the corps. The bank was approved on Feb. 23, but currently no credits have been released for sale. It is believed to be owned by Chatham County, according to the Savannah District of the corps, which must approve the landowner’s request to release the credits before they may be sold.

“We will need to see when credits will be available for purchase from the mitigation bank and that they are not being held for some other project,” said Samay in an email Friday.

The project to rebuild the bridge could go out to bid in June. The existing 58-year-old structure, which currently carries 19,000 vehicles per day, will be torn down after the new bridge is operational.

The construction is estimated to cost $16.5 million, with South Carolina paying 10 percent and Georgia paying 90 percent. Federal funding for the project is about $9 million.